Under place of birth, instead of the likes of Birkenhead, Basildon or Bournemouth, it is marked as “on an aeroplane 10 miles south of Mayfield, Sussex”.

What the document does not note is that she was delivered at 7,000 feet above the ground in the first class cabin of a Boeing 747.

Shona celebrated her 18th birthday with British Airways cabin crewCredit:
British Airways

Owen, now 26, is one of very few people on the planet, nay, in history, to have been born on a plane. As commemoration, her parents gave her names Shona Kirsty Yves, the initials spelling out SKY.

It was in 1991 that Deborah Owen, who was flying back to the UK from work in Accra, Ghana, went into labour six weeks before her due date. Wym Bakker, a Dutch doctor travelling on the aircraft delivered the baby with help from the cabin crew.

If we reached Paris, we wouldn't stop but would make a dash for LondonDeborah Owen

Owen first alerted staff on-board that she thought her baby was coming somewhere over Algeria, but the captain told her to try to hold on. It was not until she was told the aircraft had passed Paris that she could hold on no longer.

"I willed the plane to hurry," she told the Guardian in 2014. "I knew I couldn't hold on much longer. We flew over Madrid and the captain explained that, if we reached Paris, we wouldn't stop but would make a dash for London.

A woman known only as Mrs Sabbagh gave birth on a flight from Dakar and Casablanca in 1996, at 36,000 feetCredit:
Credit: ZUMA Press, Inc. / Alamy Stock Photo/ZUMA Press, Inc. / Alamy Stock Photo

"Soon the urge to push became unbearable. When the captain at last told me we had passed Paris, I knew the baby wouldn't wait any more.

“The captain was over the moon, and announced that a new passenger was on board. Everyone clapped and champagne was served all round. Half an hour later we landed at Gatwick.”

Nafi Diaby, flying with Turkish Airlines from Guinea to Burkina Faso, went into labour shortly after take-off. The baby girl was born at 42,000 feet with assistance from fellow passengers and the cabin crew.

British Airways told Telegraph Travel it had “certainly had some [births] over the years, but none recently”, while Virgin Atlantic said it had had two babies born on board, the first in 2004.

“The first one was a number of years ago and the lady named her Virginia,” a spokesperson said, “so we then named an aircraft Virginia Plane.”

It is stories such as these that validate the training in delivering babies given to cabin crew at all airlines, though some carriers have different rules on when pregnant women are allowed to fly.

“Most airlines will not allow you to travel after week 36 of pregnancy, or week 32 if you’re pregnant with twins or multiples,” says NHS guidance. Ryanair requires expectant mothers past 28 weeks to carry a “fit to fly” letter from a doctor.

How do they decide the baby's nationality?

One of the reasons Deborah Owen was flying home pregnant was she wanted her baby to be born in the UK and receive Britain citizenship, something she achieved, though her birth had to be registered by the Civil Aviation Authority.

But what of those born in international waters or over a country of no relation to the mother?

“There are several different factors to take into account when a child is born on a flight,” says Vaibhav Tanwar, a senior immigration caseworker at Visa and Migration, an immigration and nationality law specialists.

“Firstly, if the flight is from a country signed to the Convention on the Reduction of Statelessness agreement, then the child will be a national of where the airplane is registered.

“If the country is not part of the agreement, then the location of the airplane within international airspace will be the child’s nationality. For example, if a child is born with USA airspace they would become an American national. However, if that country doesn’t allow the child born in the country to become a citizen, it will then adopt the nationality of either the mother or father.”

“The same rules apply to babies born on cruise ships. Births tend to be more common at sea, due to the duration of journey.”

The issue is broadly split between two principles - jus sanguinis and jus soli, right of blood and right of soil, respectively. The former means citizenship is determined not by place of birth but by the nationality of the parents, while the latter is the reverse.

In 2015, a birth on a China Airlines flight from Taipei bound for Los Angeles became controversial after the mother was accused of attempting “birth tourism”, a trend whereby expectant parents fly to the US with the hope that their baby might be eligible for American citizenship.

Do the babies get free flights for life?

Citizenship aside, it was once thought that all babies born on planes received free flights for life. Well, perhaps, but it’s not a likely enough possibility to change your birthing plan for.

Shona Owens was given two free return flights to anywhere in the world by British Airways on her 18th birthday, but “no free flights for life”, the airline told us. Virgin, too, said air-born babies would not receive free flights for life.

Not so for a baby born on Libyan airline Buraq Air, awarded free flights for life last year. The only other carriers to have been known to do the same are Thai Airways, Asia Pacific Airlines, AirAsia and Polar Airlines. Virgin Atlantic gave Virginia free flights until the age of 21.